/*
   Copyright (c) 2012 Mizar Tools Contributors (mizartools.org)

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/
/*  Contributors :
 *	2012-04-01 Marco Riccardi - initial implementation
 *
 */
package org.mizartools.system.xml;

import java.util.LinkedList;

import org.mizartools.system.ElementParseException;
import org.mizartools.system.IElement;
import org.mizartools.system.INode;
import org.mizartools.utility.xml.XMLAttribute;
import org.mizartools.utility.xml.XMLElement;

public class Reduction implements IElement {


    public static final String NAME = "Reduction";

    private INode parentNode;
    private String aid = null;
    private Integer nr = null;

    private LinkedList<Typ> typList = new LinkedList<Typ>();
    private Term term1 = null;
    private Term term2 = null;

    private Reduction(INode parentNode){
        this.parentNode = parentNode;
    }

    public INode getParentNode() {
        return parentNode;
    }

    public static Reduction newInstance(INode parentNode, LinkedList<XMLElement> xmlElementList) throws ElementParseException {
        Reduction reductionRegistration = new Reduction(parentNode);
        XMLElement xmlElement = xmlElementList.poll();
        if (!xmlElement.getName().equals(NAME)){
            throw new ElementParseException(ElementParseException.NOT_VALID_ELEMENT, "XMLElement is a " + xmlElement.getName() + " not a " + NAME, xmlElementList);
        }
        for (XMLAttribute xmlAttribute : xmlElement.getXMLAttributeList()){
            if (xmlAttribute.getName().equals("aid")){
                if (reductionRegistration.aid == null){
                	reductionRegistration.aid = xmlAttribute.getValue();
                } else {
                    throw new ElementParseException(ElementParseException.DUPLICATE_ATTRIBUTE_ELEMENT, "XMLElement has a duplicate attribute " + xmlAttribute.getName(), xmlElementList);
                }
            } else 
            if (xmlAttribute.getName().equals("nr")){
                if (reductionRegistration.nr == null){
                    try {reductionRegistration.nr = Integer.parseInt(xmlAttribute.getValue());}
                    catch (Exception e) {throw new ElementParseException(ElementParseException.NOT_VALID_TYPE_OF_ATTRIBUTE_ELEMENT, "XMLElement has an attribute " + xmlAttribute.getName() + " with an invalid type", xmlElementList);};
                } else {
                    throw new ElementParseException(ElementParseException.DUPLICATE_ATTRIBUTE_ELEMENT, "XMLElement has a duplicate attribute " + xmlAttribute.getName(), xmlElementList);
                } 
            } else 
                throw new ElementParseException(ElementParseException.NOT_VALID_ATTRIBUTE_ELEMENT, "XMLElement has not a valid attribute " + xmlAttribute.getName(), xmlElementList);
        }

        if (!xmlElement.isEmpty()){
            while (true){
                xmlElement = xmlElementList.peek();
                if (xmlElement == null){
                    throw new ElementParseException(ElementParseException.UNEXPECTED_END_OF_FILE, "Unexpected end of XMLElement list");
                }
                if (xmlElement.getName().equals(NAME) && xmlElement.isEndElement()){
                    xmlElement = xmlElementList.poll();
                    break;
                }
                
                if (xmlElement.getName().equals("Typ")){
                	reductionRegistration.typList.add(Typ.newInstance(reductionRegistration, xmlElementList));
                } else if (Term.isTerm(xmlElement.getName())){
                	if (reductionRegistration.term1 == null) {
                		reductionRegistration.term1 = Term.newInstance(reductionRegistration, xmlElementList);
                	} else if (reductionRegistration.term2 == null) {
                		reductionRegistration.term2 = Term.newInstance(reductionRegistration, xmlElementList);
                	} 
                	else {
                		throw new ElementParseException(ElementParseException.NOT_VALID_ELEMENT, "XMLElement list contains much <Term> in element " + NAME, xmlElementList);
                	}
                } else
                    throw new ElementParseException(ElementParseException.NOT_VALID_ELEMENT, "The XMLElement " + xmlElement.getName() + " is not valid in " + NAME, xmlElementList);
            }
        }

        return reductionRegistration;
    }

    public LinkedList<XMLElement> getXMLElementList() {
        LinkedList<XMLElement> xmlElementList = new LinkedList<XMLElement>();
        XMLElement xmlElement = new XMLElement(NAME);
        if (this.aid != null) {
            XMLAttribute xmlAttribute = new XMLAttribute("aid", this.aid);
            xmlElement.getXMLAttributeList().add(xmlAttribute);
        }
        if (this.nr != null) {
            XMLAttribute xmlAttribute = new XMLAttribute("nr", this.nr);
            xmlElement.getXMLAttributeList().add(xmlAttribute);
        }
        boolean isEmpty = !(!typList.isEmpty() || term1 != null || term2 != null);
        xmlElement.setEmpty(isEmpty);
        xmlElementList.add(xmlElement);
        for (Typ typ : this.typList){
            xmlElementList.addAll(typ.getXMLElementList());
        }
        if (this.term1 != null){
            xmlElementList.addAll(this.term1.getXMLElementList());
        }
        if (this.term2 != null){
            xmlElementList.addAll(this.term2.getXMLElementList());
        }
        
        if (!isEmpty) { 
            xmlElement = new XMLElement(NAME);
            xmlElement.setEndElement(true);
            xmlElementList.add(xmlElement);
        }
        return xmlElementList;
    }

    public String getAid(){
        return aid;
    }
    
    public Integer getNr(){
        return nr;
    }

    public LinkedList<Typ> getTypList(){
        return typList;
    }
    
    public Term getTerm1(){
        return term1;
    }

    public Term getTerm2(){
        return term2;
    }

	@Override
	public void accept(Visitor visitor) {
		if (visitor.visit(this)) {
			for(Typ typ: this.typList) {
				typ.accept(visitor);
			}
		}
		visitor.endVisit(this);
	}

	@Override
	public String toString(){
		ToStringVisitor toStringVisitor = new ToStringVisitor();
		this.accept(toStringVisitor);
		return toStringVisitor.toString();
	}

}
